Electronic devices, such as smart phones, personal digital assistants, laptop computers, tablet computing devices, automated teller machines, transaction card readers and the like often require a user to enter a passcode in order to use the device. For example, when using a transaction card reader to perform a debit card transaction, the card user may be prompted to enter a personal identification number (PIN) via a keypad. Similarly, a user of a smart phone may secure the device with a passcode, and the device may require the user to enter the passcode before the device will allow the user to access the device's resources.
A problem with standard passcode entry interfaces is that an observer who watches the user enter each passcode element (i.e., a number, a letter and/or the like) into the interface may discover the user's passcode. In addition, if a user of a device does not periodically change the passcode, an observer could look for physical markers of passcode entry (such as finger-oil residue) and use those markers to discern the passcode.
This application describes methods and systems that may address issues such as those described above.